An Unpleasant Trick !!!

One day, Ebru asks her friends to give her their watches to play a trick
on them.Just not to make Ebru upset Erdoğan,Gizem,Furkan and Berkay without
knowing what they will face give her their watches.Ebru sets the watches that
she had taken from her friends a few minutes backward.
Before Ebru borrows Erdoğan,Gizem,Furkan and
Berkay’s watches,their watches show the correct time as they are written below
:
Erdoğan’s watch is 3 minutes back from the actual
time.
Gizem’s watch is 10 minutes back from the actual
time.
Furkan’s watch is 4 minutes back from the actual
time.
Berkay's watch is 9 minutes back from the actual
time.
When Erdoğan,Gizem,Furkan and Berkay take their
watches from Ebru,they realize that there is something wrong because it has
already been too late and they had realized what was wrong too late.
So, in accordiance to this:
1)When Erdoğan’s watch shows 12.35, what time does
Furkan’s watch show?
2)When Berkay's watch show 15.30, what time does
Gizem's watch show?
3) If these four friends went to meet each other
at an arranged time ,what time difference would there be between the one who
comes the second and the one who comes the fourth? ( Taking their own watches’
time in to consideration)

Tial Project Team :)